I have a Rainier cherry tree, which started with a huge crop of cherries this year but most of them died off in early stage. Of the remaining ones, I am finding this, strange markings on practically every single one. What are they? Worms, bird bites..... fungal infection I can't tell. I have to say its disappointing, whatever is doing it is remarkably thorough, because I've only found 2 that haven't been marked like this.